+/* Replace the free_user callback by "free_user".
+ */
+__isl_give isl_id *isl_id_set_free_user(__isl_take isl_id *id,
+ __isl_give void (*free_user)(void *user))
+{
+ if (!id)
+ return NULL;
+
+ id->free_user = free_user;
+
+ return id;
+}
+
+/* If the id has a negative refcount, then it is a static isl_id
+ * and should not be freed.
+ */